It happens in the northern hemisphere when the sun's vertical rays pass over the Tropic of Cancer. 2. At this moment, all places north of the Arctic Circle (66.5o N latitude) get 24 hours of daylight (June 21, June solstice). South of the line, it is night all day and around the world, the days are getting shorter.
The sun reaches its highest point in the sky at midday on June 20th, and starts to drop down towards the horizon before starting up again at midnight on July 23rd. So the period from June 20th to July 23rd is 1 day, 12 hours and 45 minutes long.
In other words, a day on the Tropic of Cancer is about 8 hours long.
According to NASA, "the average daily temperature near the tropics is close to 70 degrees F (21 degrees C), which means that most people would be sweating if they were out in the sun for eight hours straight."
But it doesn't have to be hot for your body to need water. Even at 60 degrees F (15 degrees C), you'll start to feel the effects of dehydration after about seven hours without drinking anything. And at 50 degrees F (10 degrees C), you'll begin to suffer problems after only four hours without water.
Your body is made up of approximately 69 percent water.
The sun's vertical rays touch the Tropic of Cancer, a line 23.5 degrees north of the equator, on the June solstice. In the Southern Hemisphere, June 21 marks the beginning of winter and the shortest day of the year. The night is longer than the day, and at mid-summer it begins to get lighter earlier each morning.
In the Northern Hemisphere, the summer solstice is when the sun is highest in the sky and days are longest. At midsummer, the sun is directly over the northernmost point of Africa and Asia and around 15 degrees south of the horizon in Europe. It takes six months for the earth to rotate around the sun, so the summer solstice will not be again until December 22nd next year.
The September equinox occurs when the sun is centered exactly between the Earth and the moon. The crescent moon and half-full moon occur during this month and the nights are equally dark.
The November equinox happens when the sun is located directly over the equator, and the days are equal in length. The full moon during this time is called the "moonless" or "lunar" full moon because there is no new moon or first quarter.
The March equinox marks the return of daylight to the Northern Hemisphere after the winter solstice.
The 21st of June The Tropic of Cancer is the circle drawn at 23.5 degrees north latitude, where the sun is directly overhead at noon on June 21, the first day of summer in the northern hemisphere. At this location, around 30 degrees north of the equator, days are approximately six hours long and nights are about six hours short of being able to see its whole way around the earth.
In terms of distance, the sun is 400 million miles from Earth. It takes our stara little over eight minutes to rotate once around its axis, which is why we have daytime and nighttime. The sun appears to move across the sky because it is actually staying put while everything else around it is moving.
At any given moment there are two points on the sun that are exactly opposite one another, with respect to the direction they are facing. These points are called the solar poles. The part of the sun's surface that is not covered by clouds or other material reflecting light into space forms a sort of dome, like a ball, around these two points. This is called the solar corona.
The solar corona has three main layers: the chromosphere, the transition region, and the photosphere. The chromosphere is the lowest layer of the corona and it is made up of ionized gas called hydrogen ions.